One interesting fact I learned. all things being equal, is that revolvers are more tolerant of neglect.

All firearms should be regularly maintained and cleaned, and nowadays, reliability is about the same; however, you can park your revolver, and forget about it, until needed.

Revolvers can handle a bit of dirt, or infrequent care a bit better. fewer moving parts, springs, and sliding bits to foul up... it takes a really shoddy revolver to be prone to malfunctions. cheap semi autos are notoriously unreliable. When I did collect guns, and bought a few cheap ones for some odd reason. I've had firing pins snap, springs break, magazines that did not feed properly, etc...misfeeds, and extraction problems are fairly rare unless the gun is VERY cheap, or old and neglected. For comparison, my revolvers have misfired three or four times, and each tie it was defective ammo that was responsible.

I've carried several handguns while working various jobs. I've always preferred revolvers when I could get them. once you load them all you have to do is aim and pull the trigger. For most situations, six rounds is plenty If you even have a chance to get off one shot in a self-defense situation you are likely to end the fight at that point. even if you miss the 'bad guy" is likely to haul butt out of the area.The average thug, crook, etc...is not going to engage in an extended shootout. SO I go with simple to operate and reliable.

However, a semi-automatic is better for tactical use. the extra capacity, the rate of fire and speed of reload gives it a distinct advantage.

So It's sort of a pick te gun that's best for the job situation..neither one is superior in all situations.

its a safety issue for civilian firearms, no one wants it going off because John Q hunter forgot to take his finger off the trigger.Or wasn't taught not to touch the trigger unless you want the gun to go boom.

I know that some lever actions could be fitted with a little metal tab that pulled the trigger when you worked the lever. allows very rapid, if incredibly inaccurate fire. butif you are firing at close range sometimes putting more rounds in the air helps.

My feeling is that anyone who's serious about committing battery will have something on that will take the brunt of anything too shocking.

Law level six sounds like something currently ongoing in the United Kingdom; widespread surveillance, and every firearm has to be registered, and you need a reason to possess it.

The exception would be shotguns, with the limitation that it can only have a magazine capacity of two, plus one in the chamber; they'd still need to be registered, but the authorities would need to give a reason to deny anyone to own one.

Single shot rifles, possibly semi-automatic ones with an underpowered calibre for sports.

Historical working firearms, though considering the fact we have man portable fusion guns, historical may be limited to technological level four.

One exception could be black powder weapons, including pistols and revolvers that have to be loaded that way.

You can't fire both simultaneously, since I suspect they'd interfere ballistically with each other, but it's still pretty fast.

Seven rounds and one chambered in each magazine.

You could load each magazine with a different type of ammunition, like one armour piercing, and the other high explosive; one makes a hole, the other exploits it.

I've seen this one test field a few times. It's an interesting idea but the review seems to be unfavorable. the added complexity of the internals and the added weight make it heavier and more expensive than two shotguns. One of the biggest problems is that you can only fire the barrels in a back and forth sequence. And both barrels load at the same time. If you fire one barely and reload, the second barrel ejects its shell whether you have fired it or not.

f you could select which barrel was firing and reload barrels selectively then it would be a bit more useful.

A suitport or suitlock is an alternative technology to an airlock, designed for use in hazardous environments and in human spaceflight, especially planetary surface exploration. Suitports present advantages over traditional airlocks in terms of mass, volume, and ability to mitigate contamination by—and of—the local environment.

Operation[edit]
In a suitport system, a rear-entry space suit is attached and sealed against the outside of a spacecraft, space habitat, or pressurized rover, facing outward. To begin an extra-vehicular activity (EVA), an astronaut in shirt-sleeves first enters the suit feet-first from inside the pressurized environment, and closes and seals the space suit backpack and the vehicle's hatch (which seals to the backpack for dust containment). The astronaut then unseals and separates the suit from the vehicle, and is ready to perform an EVA.[1][2][3]
To re-enter the vehicle, the astronaut backs up to the suitport and seals the suit to the vehicle, before opening the hatch and backpack and transferring back into the vehicle. If the vehicle and suit do not operate at the same pressure, it will be necessary to equalize the two pressures before the hatch can be opened.
Advantages[edit]
Suitports carry three major advantages over traditional airlocks. First, the mass and volume required for a suitport is significantly less than that required for an airlock. Launch mass is at a premium in modern chemical rocket-powered launch vehicles, at an estimated cost of US$60,000 per kilogram delivered to the lunar surface.[4]
Secondly, suitports can eliminate or minimize the problem of dust mitigation. During the Apollo program, it was discovered that the lunar soil is electrically charged, and adheres readily to any surface with which it comes into contact, a problem magnified by the sharp, barb-like shapes of the dust particles.[5] Lunar dust may be harmful in several ways:
The abrasive nature of the dust particles may rub and wear down surfaces through friction.
The dust may damage coatings used on gaskets, optical lenses, solar panels, windows, and wiring.
The dust may cause damage to an astronaut's lungs as well as nervous and cardiovascular systems, leading to conditions such as pneumoconiosis.[6][7]
During the Apollo missions, the astronauts donned their space suits inside the Apollo Lunar Module cabin, which was then depressurized to allow them to exit the vehicle. Upon the end of EVA, the astronauts would re-enter the cabin in their suits, bringing with them a great deal of dust which had adhered to the suits. Several astronauts reported a "gunpowder" smell and respiratory and/or eye irritation upon opening their helmets and being exposed to the dust.[5]
When the suit is attached to the vehicle, any dust which may have adhered to the backpack of the suit is sealed between the outside of the backpack and the vehicle-side hatch. Any dust on the suit that is not on the backpack remains sealed outside the vehicle. Likewise, the suitport prevents contamination of the external environment by microbes carried by the astronaut.
Additionally, the suitports significantly reduce the ingress and egress time, and virtually remove the need of pumpdown of the airlock, which normally is either associated with air loss, or requires heavy and complex pumping machinery as the only space that needs to be pressurized is the area between the vehicle hatch and the life-support backpack, and even that only in case of need for repairs, decontamination and refitting of the suit.[1][3]
Development and use[edit]

Suitport concept being tested with the Z-1 prototype spacesuit in 2012
A patent for a suitport was first filed in 1987 by Marc M. Cohen of NASA's Ames Research Center.[8] Further patents were filed in 1996 by Philip Culbertson Jr.,[1] and in 2003 by Joerg Boettcher, Stephen Ransom, and Frank Steinsiek.[2]
As of 1995, suitports have found a practical, terrestrial application as part of a NASA Ames hazardous materials vehicle, where the use of the suitport eliminates the need to decontaminate the hazmat suit before doffing.[9] A suitport prototype built by Brand Griffin has been used in a simulated lunar gravity test on board NASA Johnson's C-135 aircraft.[9]
Suitports may find use as part of future NASA projects aimed at achieving a return to the Moon and manned exploration of Mars. NASA's conceptual Space Exploration Vehicle has two suitports on the back of the craft.
Testing has been taking place in combination with the Z-1 prototype spacesuit inside NASA's human-rated thermal vacuum chamber B at the Johnson Space Center.[10] Early unmanned tests of the suitport were conducted in June 2012.[11][12] The first manned tests of the suitport occurred on 16 and 18 July 2012; during these manned tests the spacesuit was kept at a pressure of 14.7 psi (1 atm) with the chamber pressure at approximately 6.5 psi (0.44 atm), equivalent to an altitude of 21,000 feet (6,400 m).[12] Future manned tests were planned for September and August 2012, where NASA planned to keep the spacesuit at a pressure of 8 psi (0.5 atm) and the vacuum chamber at roughly 0 psi (0 atm).[12] Suitports may eventually be tested on the International Space Station.[13]

More likely used dirtside, or on a spacestation, which it's why it's here.

You could do this on a spaceship, but likely it would be in an additional recessed bay; the advantage would be not having to cycle the airlock.